Twenty to 30 per cent appears to be lost, according to a crops report from the Ontario Ministry of Agriculture, Food and Rural Affairs.
Normally 10 per cent or less fails to make it through winter.
Part of the problem was late seeding and fields planted in October are not looking good. Some will be written off.
In other cases, if farmers need straw, they are seeding oats into the bare patches.
Ice sheets also took out a lot of wheat.
Corn and soybean planting has begun in some of the warmest and lightest soils in the southern part of the province, but most areas remain delayed by cold and rain.
